Ask a Dog Vet and Get Answers to Your Dog Veterinary Questions
I am sorry to hear you are worried about Baby. I am Rebecca; I am a veterinarian and will do my best to help.
What part of his leg did your veterinarian tell you was injured, or wasn't he sure? Getting a diagnosis of the exact problem is the best way to know how to treat.
The things we see in hind legs of young dogs are panosteitis (usually large breed dogs, very painful but goes away after a few weeks or so), and abnormalities of bone formation like OCD lesions in the hip or knee (also do not get better with time), or injuries like pinched nerves, sprains, tendon or ligament injuries (usually get better with time, but can take months). I assume there are no broken bones since Xrays were taken. One thing we see in small breed dogs is "aseptic necrosis of the femoral head" where the top of the thigh bone, where is connects to the hip, loses its blood supply and that part of the bone dies and is very painful. It can be hard to see on Xrays. The treatment for this condition is surgery; it does not get better with time.
It might be worth it to send the Xrays to a specialist for a second opinion.
Any chance you could get the Xrays, and post them here or on the Internet, and send the link to me?
How is Baby doing? Rebecca